1. Field of Invention
The present invention relates to a tire pressure detecting apparatus, and more particularly to a tire pressure detecting apparatus that is capable of detecting carrier waves.
2. Description of the Related Art
With reference to FIG. 5, a tire pressure monitoring system (TPMSs) comprises multiple tire pressure detectors (51) and a monitoring apparatus (53). The tire pressure detectors (51) have non-identical ID numbers therein and are installed respectively inside tires (52) of a vehicle (50) to continuously detect tire pressure inside the tires (52). The monitoring apparatus (53) is normally installed inside the vehicle (50), receives a wireless signal corresponding to the detected tire pressure inside the tire (52) from the tire pressure detector (51), and displays the detected results for driver observation.
Each tire pressure detector (51) and the monitoring apparatus (53) communicate by one-way transmissions. The tire pressure detectors (51) may send wireless signals to the monitoring apparatus (53) at the same time so that the monitoring apparatus (53) gathers incorrect messages due to interference between the wireless signals.
To overcome the interference problem, a tire pressure detector may send the same data to the monitoring apparatus (53) eight times interspaced by an interval. Despite resolving interference problems, power loading of the tire pressure detector is increased, thereby reducing lifetime and reducing intervals between servicing or increasing costs due to larger battery installation.
The present invention provides a tire pressure detecting apparatus to obviate or mitigate the shortcoming of the conventional tire pressure detector.